Most, by far, videos of actual shootings show two handed shooting, or at least the opportunity to use it if desired.

One handed shooting has it's place for sure, and should be practiced. But should be secondary to two handed shooting. With so much emphasis on situational awareness, that awareness can provide time for a two handed shooting stance, if not extracating one from the situation beforehand.

There are some pretty good shooting instructors and schools out there, and none emphasize one handed shooting over two handed.